A satellite radio-navigation system comprising a central station in which are remotely carried out some or all of the radio-navigation calculations usually carried out by a receiver necessitates a specific communication link between the GNSS terminals and the central station. This link is typically a narrow band link, for example a VHF link which is limited to a frequency band of less than about one hundred kHz. However, a satellite radio-navigation signal is a wide band signal which necessitates several MHz of bandwidth and its transmission on a narrow band link therefore necessitates an adaptation, in other words a compression, making it possible to transmit all of the useful information contained in the signal on a transmission channel which is not naturally compatible with the wide band of the signal.
A known solution for transmitting a GNSS on a narrow band channel consists of sending data in bursts in a non-continuous manner. This solution necessitates synchronization of the burst transmission with the useful data transmitted by the satellite in order not to cause loss of information.
The invention proposes a solution that is different from the known ones and which makes it possible to continuously transmit a wide band GNSS signal on a narrow band transmission channel by carrying out a compression of that signal. Moreover, the invention also makes it possible to carry out the calculation of the correlation function of the GNSS signal directly on the received compressed signal in an optimum manner.